Bug 6874: QA follow-up

Bug 6874: QA follow-up

Squash of the following commits:
  return with explicit undef removed
  Follow-up for PBP fixes
  follow-up fix POD syntax
  follow-up jquery has moved

Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>
Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Amended: removed POD changes in Biblio.pm while rebasing.
Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>